The American stand-up comedian Greg Proops has been resisting offers to host British game shows for years. "You can't really get up on stage and tell people that everything they believe in is screwed if you're on television giving away refrigerators," he confides.

He has finally broken his pledge for Space Cadets, a panel-game that crosses Blake's Seven with Have I Got News for You. "As you know on this island, games are more important and indeed better than life itself," Proops explains. "They have a beginning, middle and end. As we say in the States, there's closure. But it's not a game show; it's a comedy show with a sci-fi twist."

With Proops as chairman and Craig Charles and Bill Bailey as team captains, comedy is certainly to the fore. Competitors have to play such games as "Mind Your Klingon" (translating Klingon into English) and identify stills from such deathless works as Santa Claus Conquers the Martians and Killer Tomatoes Eat France. The regulars are aided and abetted by stooge - sorry, guest - appearances from such sci-fi superstars as William Shatner (Star Trek), Sylvester McCoy (Dr Who) and Claudia Christian (Babylon 5), and writers such as Terry Pratchett, Iain M Banks and Rob Grant (Red Dwarf).

"Shatner was a love bug," Proops drools. "Everybody was telling me he's difficult but he couldn't have been more up for it. He got up and danced at one point, and his second game turned into a melee. He's a kook with a good sense of humour. He has no bitterness; he never says he's sick of Captain Kirk. We took the piss - with respect, but we still took the piss. He seemed happy as a clown to do stuff about Star Trek. He was even dissing other crew-members. The papers had a go at him because he's going through a divorce, wears a toupee and is fat. Well, so what? He's 60-something now. He's in the last third of his life and he doesn't have to take his shirt off to chase Romulans any more."

Space Cadets also taps into the current mania for sci-fi. An Open University lecture on quantum physics delivered by Mulder and Scully would probably get astronomical ratings in the present climate.

Why have we become such sci-fi obsessives? "Paranoia and anti-government feeling are necessary now that people have lapsed into complacency," Proops reckons. "Also, we're tired of empirical explanations for everything. People like monsters and mythic heroes and villains that they can hang on to."

Alan Clements, the producer of the show, echoes his presenter. "People do have a sense of wonder about the world around them," he says. "They don't think everything is cut and dried."

Hard-core fans come with the sci-fi territory. Recordings of Space Cadets were attended by people dressed as Star Trek crew members and Klingons. Clements knew what he was getting into when he went to a sci-fi convention in Winnipeg and encountered a fan translating the New Testament into Klingon.

He was keen to stay on the right side of these people. "The sci-fi community were suspicious," he concedes. "Their fear was that we might be teasing them for being sad losers. But the key is that we're not laughing at sci- fi - we're laughing with it. The show is for people who really enjoy sci- fi but can appreciate the ropiness of something like the costumes and props in Space 1999."

Are we in danger of overdosing on comedy panel-games? "Of course we are," says Proops. "There are too many comedy shows in general, but this is on in the early evening when people aren't inundated with panel games." Proops claims that this self-awareness actually helps the programme. "Everybody's hipper than everybody else now," he concludes. "There's no more hidden anything. We're post-modern and self-referential. We had William Shatner on doing jokes about Kirk. I looked at the camera and thought, `I'm riffing with Captain Kirk'. You don't expect that in your life."

`Space Cadets' starts on Tue at 6pm on C4